T12 tip heating speed is very fast, when the new solder tip connect the electricity, it must be tinput immediately to the solder tip, for protection, due to heating up fast, just need 6-10 seconds, no have more time to you for preparetion.

　　so the important is prepare the items which will be welded, and finally boot power, and each welding gap or the end, should be more on the tin to protect and then shutdown, so it can avoid to tin the new sold tip is difficult, especially the T12 tip type of iron, such as T12-I / T12-IL / T12-BL / T12-ILS and so on!